Anesthetic apparatus



A. c. CLARK.

ANESTHETIC APPARATUS.

APPL1cAT1oN HLED 11111118.1914.

Patented May 4, 1920.

2 SHEETS-SHEET l.

A. c. CLARK.

ANESTHETICVAPPABATUS. APPLICATION FILED MAY Is. 1914.

y 2 SHEETS-SHEET 2.

Ez ven for Z6 NITED OFFICE.

ALBERT CHARLES CLARK, or CHICAGO, ILLINOIS, A'ssIeNOR To A. C. CLARK aoo., OF CHICAGO, ILLINOIS, A CORPORATION or ILLINOIS.

ANESTHETIC APPARATUS.

Specification of Letters Patent.

Patented May 4:, 1920.

Application filed May 18, 1914. Serial No. 839,228.

To @ZZ lw/wm it may concern.'

Be it known that I, ALBERT CHARLES CLARK, a citizen of the UnitedStates, residing at Chicago, in the county of Cook and State Oi"lllinois, have invented certain new and useful Improvements inAnesthetic Apparatus, of which the following is a specilication.

My invention relates to apparatus for administering a mixture ofnitrous' oxid and oxygen gases for producing analgesia and anesthesia,as widely practised in dentistry, and also to some extent in surgery,and particularly concerns the provision of e'liicient and sensitivemeans for reducing and regulating the pressure of the gases which passfrom the compressed gas cylinders to the gas bags of apparatus of a wellknown type, in general similar to that shown and described in my pendingapplication for Patent No. 686,252, so that a uniform pressure may bemaintained in each bag and the proper proportion of each gas may pass toand through the mixing passages of the apparatus to the breathing orinhaling devices. Prior to my invention pressure-reducing and regulatingdevices have been employe/d which have employed a diaphragm acted uponby the gas admitted under high pressure to an expansion chamber andcontrolling the reducing valve opening; but the use of a diaphragm,which l have avoided in my present invention, is objectionable becauseof the danger of rupturing the diaphragm or of distorting it beyondusefulness, and because the irregular and sudden expansive action of thecompressed gas entering the expansion chamber is liable to cause achattering of the valve which strains the diaphragm and impairs theuniformity of action of the valve, and because such valves, asheretofore constructed, are peculiarly liable to freezing, as a resultof the cold produced by the sudden expansion of the gases adjacent therestricted passage leading into the diaphragm chamber. j

The object of my invention is to provide j nessure-reducing andregulating means free from the objections'to prior apparatus abovementioned, and which shall have various advantages and features ofnovelty and utility which will beapparent from the descriptionhereinafter given, and the essential elements of which are pointed outin the appended claims.

In the drawings, Figure 1 is a top plan -view of an anesthetic apparatusin which my invention is embodied; Fig. 2 is a section on the line 2-2of Fig. l; Fig. 3 is a section on the line 3-3 in Fig. l;l and Fig. 4 isa section of the reducing valve, in the same plane as Fig. 2 but on alarger scale; and Fig. 5 a detail showing the scale for the adjustingcollar.

rlhe same letters of reference indicate the same parts in the severalfigures of the drawings. Y

In order to make clear the present invention it will be necessary tobriefly describe anl anesthetic apparatus to which it may be applied, orin which it may be` embodied. From the base of the apparatus (not shown)rises a post l, upon the top of which is mounted a casing 2 having twoextensions 2. with two passages 3 and 4, communicating one with thesupply of nitrous oxid and one with the supply of oxygen, andcommunieating respectively with ports 5, 6, both or either of which areadapted to be placed in V communication with a large port 7 in one sideof a hollow plug valve 8, the other side being provided with a port 9communicating with mixing passages 10 on the inside of the casing, tl emixed gas passing from the casing'through` the gas administering hose llto a suitable inhaling device. The handle l2 of the mixing valve isprovided with a lsuitable indicating device and dial marked to indicatethe different positions of the valve, and the relative proportions ofthe 'different gases admitted at such positions.

In the form of apparatus shown, .each of the extensions 2u of the casingsupports at its sides a pair of opposite tubes or arms 13, 13, each ofthe Outer ends of which terminates in a closed yoke 14- adapted toreceive the head of a gas cylinder 15. The arms of one extension aredesigned to receive cylinders containing nitrous oxid, and the othercylinders containing oxygen, under the usual high degree of compressionOf from about nine hundred to fifteen hundred pounds to the square inch.Transversely arranged with respect to the arms, 13, 13 and extending inopposite directions from what may be termed the outer ends of theextensions 2a, are arranged two tubes or arms, 16, 16 to the outer endsof which the gas bags 28, 28 for nitrous oxid and oxygen, respectively,are secured. The ports and passages for controlling and supplying thetwo O'ases may be, and are in the apparatus described, alike, and forconvenience of description and illustration, similar parts are numberedalike, excepting that the parts relating-sto the distribution of onegas, as oxygen, are marked with prime, while the parts relating to thedistribution of nitrous oXid are not so marked.

One feature of my present invention re-A lates to a provision forsupplying each of 'the different gases either' through throttled,

thoughk unregulated passages, or through the regulating and reducingvalve which is the principal feature of my invention. The passages forthe direct flow of gas-will-therefore now be described.

rlhe head 17 of each gas cylinder is formed in the usual manner with anoutlet passage governed by an outlet valve and permitting a throttledflow of gas through a supply passage extending at right angles to theoutletpassage. The outer end of each tubular arm 13 is formed with ahorizontal bore within which is arranged a valve bushing 18communicating with a block 19 arranged. to rest against the inner faceof the yoke 14 and which is formed with a passage communicating with thesupply passage of the gas cylinder. A nut 20 is provided to clamp thevvalve bushing in place in the bore in the arm 13. A rotary or plug valve21, in the present instance, though not necessarily,

- tapered in shape, 1s seated in the bushing 18 and is equipped with ahandle 22 by means of which it may be turned to admit the gas into theinterior passage of the arm or tube 13.

The inner ends ofthe passages in the pair' of tubes 13 communicate withan annular passage 23, such passage lying between the tube 16 associatedwith thev tubes 13 and an inner tube 24, this latter tube being incommunication with the passage 3 (or the passage 4, as the case may be)of the casing. The outer end of the annular passage Q3 is incommunication, through the passage 25, and connecting open passagesthrough the casing of the reducing and regulating valve which will laterbe described, with the gas bag 23, and also with the passage through theinner tube 24, the result of this arrangement being that under thedirect, though throttled flow of gas thus far described, the gas bagwill act as an elastic reservoir for gases passing through the directflow valve 21 to and through the mixing valve 8. 1n the passage throughwhich flows the oxygen gas, a check valve 27 is provided intermediatethe gas bag and inner tube 24', to prevent a back flow of gas, but inthe present instance the passage for the nitrous oxid gas is left whollyunobstructed.

The casing of the reducing and regulatydrical portion havingscrew-threaded engagement with the approximately cylindrical uppermember and a depending irregular gooseneck portion to which the nozzleof the gas bag 2S is secured. The interior of the tube 16 andthe innertube 24 are bothin communication with the gas bag through a series ofducts 31, a chamber 32, and a passage 33 in the depending gooseneckportion of the casing. Through passages in the block 19 and a pipe 34,communication is provided for the passage of gas from the cylinder 15 toa passage 35 formed in the casing member 29. The lower end of surhpassage terminates in a'coned inlet nozzle 36 secured' in said casingmember and hav-A ing a restricted or contracted gas port.

The lower part of the chamber 32st the casing is formed with ascrew-threaded opening for the reception of an eXteriorly threadedbushing 37 which has at its outer end au interior coned surface adaptedto receive packing 37a and a cylindricalr bore forthe reception of aplunger 38. A packing nut 39, perforatedto receive the plunger 33, isprovided to inclose and compress the packing. The upper end of theplunger is equipped with a valve seat 40, which is preferably formed ofa fiber composition or material having similar characteristics, and theplunger is pressed downward to normally open communication through thevalve by a compression spring 41interposed between the valve casing anda shoulder on the plunger. The lower end of the plunger is bored toreceive a sliding plug 42 formed with a shoulder near its lower end anda coned bearing below such shoulder, which plug normally is yieldinglypressed' downwardly by a relief spring 43 so that the shoulder willcontact with a cap 44011 the plunger constituting a stop for the plug.The spring 43 is-of suiiicient strength to force the plunger 328 upwardagainst the stress of the spring 41 and maintain the valve seat 40 inclosed position aga-inst the valve nozzle 36 in the normal operationofthe reducing valve mechanism, but when the plug 42 is forced to astill more elevated position', as hereinafter explained, the spring willbe compressed, andinjury which would other'- wise be done to the' valveseat is avoided.

The plunger 38 is raised and lowered, to eil'ect a regulated supply ofgas through the valve 36, throughthe expansion of the gas bag 218. Tothis end a frame 45 is provided, this frame having at its lower centralportion a seat arranged toV receive and coperate with the coned lowerendof the plunger, and being provided with upwardly extending arms 4Gformed with bearings in which are pivoted levers 47 having longdownwardly extendingl arms 48 terminating in disks 49 which are arrangedtobe .acted upon by the gas bag. The gas bag 1s '1nclosed in a net 50 inthe practical operation of the device, and this net is important 1nproducing an effective contact with the arms. The upper ends of thelevers 47 are fulcrumed upon the flange 5l of an adjustable collar 52,which has a screw threaded engagement with the casing member 29 so thatby turning the collar and flange may be raised or lowered to vary thefulcrum point of the lever arms.

It will be understood that the pressure in the gas bag is but slightwhen the bag is nearly deflated, but increases regularly as the bag ismore and more distended. In the apparatus illustrated and described, thepitch of the screw threads of the collar, the elasticity of the bag, andthe arrangement and adjustment of the parts is such that a turning ofthe collar through approximately three-fourths of a revolution willeffect a change in the position at which the gas bag will act on thearms 48 to shift the plunger 38 and valve seat 40 corresponding to avariation from zero pressure to a pressure of ten ounces per squareinch. A dial indicating such variation is therefore provided, thegraduations being formed on the casing member 29 and read by referenceto a pointer 53 carried by a handle 54 formed on a ring which is securedto the adjusting collar. To provide for the adjustment of the parts whenthe apparatus is assembled or a readjustment when some of the parts, asthe valve seat 40, have become worn, the handle 54 is made angularlyadjustable on the collar. In the present instance this adjustment iseffected by means of a pair of screws passing through the handle ringand adapted to engage any pair of a plurality of pairs of screw socketsin the collar 52.

In the ordinary use of my apparatus, the collar 52 of the nitrous oXidand the oxygen gas bags will be set to corresponding degrees ofpressure, and the ination and deflation of the gas bags, as the gasesare used, will open and close the regulating valves to maintain asubstantially constant degree of pressurevin the bags. If, how

-ever, as may under some conditions be desired, a direct flow of eithergas be desired the handle 22 of the direct flow valve for that gas maybe turned to admit such gas through the tube or arm 13 to the gas bag.In such case the bag will be inflated beyond the indicated setting ofthe regulating valve, or even beyond the capacity of regulation of thearms 48. The relief spring 43 will nevertheless permit an excessivespreading of the arms 48 without causing any injury to the mechanism ofthe regulating and reducing valve I claim: y

l. In anesthetic apparatus arranged to be equipped with a compressed gascylinder, a regulating valve in communication with the gas supply fromsuch cylinder, an expansible elastic gas bag constituting avariable-pressure reservoir for a relatively large volume of gas at arelatively low pressure in free communication with the gas-administeringpassages of the apparatus, a pivoted lever arranged to be rocked by saidbag as it is inflated, and a connection operated by said' lever foropening and closing said valve.

2. In an anesthetic apparatus arranged to be equipped with a compressedgas cylinder, a regulating valve, in communication with the gas supplyfrom such cylinder, an expansible elastic gas bag constituting avariable pressure reservoir for a relatively large volume of gas at arelatively low pressure in free communication with the gas-administeringpassages of the apparatus, a pivoted lever arranged to be rocked by saidbag as it is inflated, and a connection operated by said lever foropening and closing said valve, said connection including provision forvarying its adjustment with respect to said pivoted lever.

3. In anesthetic apparatus arranged to be equipped with a compressed gascylinder, a regulating valve in communication with the gas supply fromsuch cylinder, a gas bag, a plurality of levers spaced around said bagand arranged to be rocked thereby as the bag is inflated, and aconnection operated by said levers for-opening and closing said valve.

4. In anesthetic apparatus arranged to be equipped with a compressed gascylinder, a regulating valve in communication with the gas supply fromsuch cylinder, a gas bag, a plurality of levers spaced around said bagand arranged to be rocked thereby as the bag is inflated, and a yieldingconnection operated by said levers for opening and closing said valve.

5. In anesthetic apparatus arranged to be equipped with a compressed gascylinder, a regulating valve in communication with the gas supply fromsuch cylinder, a gas bag, a plurality of levers spaced around said bagand arranged to be rocked thereby as the bag is inflated, a connectionoperated by said levers for opening and closing said valve, and meansfor varying the adjustment of throw of said levers with respect to theopening and closing of the valve.

6. In anesthetic apparatus arranged to be equipped with a compressed gascylinder, a gas bag, a regulating valve in communication with the gassupply from such cylinder, a plunger equipped with a valve seat, a

series of levers spaced around said bag and arranged to be rockedthereby as the bag is inflated, and a frame pivoted to said levers andoperatively connected with said plunger.

7. In anesthetic apparatus arranged to be equipped With a compressed gascylinder, a gas bag, a regulating valve in communication with the gassupply from such cylinder, a plunger equipped with a valve seat, anadjusting ring on said casing, a series of levers each fulcrumed at oneend on said ring and having its other end arranged to be rocked by saidgas bag as it is inflated, and a frame having branches pivoted tointermediate portions of said levers and operatively conv nected withsaid plunger.

8. In anesthetic apparatus arranged to be equipped With a compressed gascylinder, a gas bag, a regulating valve in communica*- tion vvith thegas supply from such cylinder, a plunger equipped With a valve seat, aspring-pressed bearing plug slidingly arranged in the lower end of saidplunger, a pivoted lever arranged to be rocked by the inflation of saidgas bag, and a connection intermediate said lever and bearing plug foroperating said plunger and opening and closing the valve.

9. In apparatus of the character described, and including a gascylinder, an eX- pansible gas bag, and an inhaling device, a passage forthe direct floiv of gas from said cylinder to said gas bag, a directflow valve for opening and closing said passage, a second passage forthe flow of gas from said cylinder to said gas bag, an automaticregulating and reducing valve governed by the expansion of the gas bag'`and arranged to control said last mentioned passage, and a passage forthe outflow of gas from said gas bag to said inhaling device.

10. In apparatus of'v the character described, and including a gascylinder, a gas bag, and an inhaling device, a passage for the directiiovv of gas fromsaid cylinderv to said gas bag, a directl flow valvefor opening and closing said passage,. a second pas'- sage for the flowof gas from said cylinder to said gas bag, an automatic regulating andreducing valve in said last-mentioned passage, means operated by arelatively slight expansion of said gas bag for controlling saidreducing valve When the direct flow valve is closed and for closing thereducing valve and permitting a relatively large expansion of the bagwhen the direct fioiv valve is open, and passages for. the outflow ofgas from said gas bag to said inhaling device. 4

1l. In. anesthetic apparatus arranged to be equipped With a compressedgas cylinder, a gas bag, a regulating valve in communication with thegas supply from such cylinder, a plunger equipped with a valve seat, aseries of levers spaced Varound said bagk and arranged to be rockedthereby as the bag is inflated, a frame pivoted te said levers, and auniversal connection intermediate said frame and said plunger.

ALBERT CHARLES CLARK.

lVitne'sses CHARLES H. W'ARREN, J. V. HAnBERG.

